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Code Issues Projects Releases Packages Wiki Activity Actions 13

Issue #13478: merge with 3.2

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Sandro Tosi 2012-04-24 18:12:13 +02:00
commit d57c73bbdd
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Doc/library/timeit.rst
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@ -99,7 +99,19 @@ The module defines the following public class:
timeit.Timer('for i in range(10): oct(i)', 'gc.enable()').timeit()
The module also defines two convenience functions:
The module also defines three convenience functions:
.. function:: default_timer()
Define a default timer, in a platform specific manner. On Windows,
:func:`time.clock` has microsecond granularity but :func:`time.time`'s
granularity is 1/60th of a second; on Unix, :func:`time.clock` has 1/100th of
a second granularity and :func:`time.time` is much more precise. On either
platform, :func:`default_timer` measures wall clock time, not the CPU
time. This means that other processes running on the same computer may
interfere with the timing.
.. function:: repeat(stmt='pass', setup='pass', timer=<default timer>, repeat=3, number=1000000)
@ -161,13 +173,9 @@ similarly.
If :option:`-n` is not given, a suitable number of loops is calculated by trying
successive powers of 10 until the total time is at least 0.2 seconds.
The default timer function is platform dependent. On Windows,
:func:`time.clock` has microsecond granularity but :func:`time.time`'s
granularity is 1/60th of a second; on Unix, :func:`time.clock` has 1/100th of a
second granularity and :func:`time.time` is much more precise. On either
platform, the default timer functions measure wall clock time, not the CPU time.
This means that other processes running on the same computer may interfere with
the timing. The best thing to do when accurate timing is necessary is to repeat
:func:`default_timer` measurations can be affected by other programs running on
the same machine, so
the best thing to do when accurate timing is necessary is to repeat
the timing a few times and use the best time. The :option:`-r` option is good
for this; the default of 3 repetitions is probably enough in most cases. On
Unix, you can use :func:`time.clock` to measure CPU time.